Stair-tread



C. E. OLIVER.

STAIR TREAD.

APPLICATION FILED JULY 22, 1918.

0. m Q if? M L M I I P z e i 3 uw 4 m Q, {N a J. T F Q WITLED TATEsrATENT OFFICE.

cnmms E. OLIVER, or'nosron, rvmssaonusnrrs, ASSIGNOR 'ro UNIVERSAL sernry TREAD comrm, or BOSTON, MASSACHUSETTS, A CORPORATION or MASSACHU- SETTS.

STAIR-TREAD.

Specification of Letters Patent.

Patented May 18, 1920.

To all whom it may concern:

Be it known that I, CHARLES E. OLIVER,

' of Boston, in the county of Sufiolk and State of Massachusetts, a citizen of the United States, have invented. a newand useful Improvement in Stair-Treads, of which the following is a specificatiom My invention relates to metal stair treads and more particularly to treads adapted to be used on board-ship or in other places where the stair structure may consist simply of metallic side stringers for the treads and hand rails for the user. In such structures, especially on board ship, it is desirable to have something that is not only light but very strong, able to take a great deal of wear, and also able to carry what is known as a safety or non-slipping tread upon it. My present construction enables the step and tread to be made in one piece and especially by practically one operation.

My invention in its preferred form will be understood by reference to the drawings,

in which- Figure 1 is a plan showing my invention in its preferred form,

Fig. 2 being an under view thereof.

Fig. 3 is a front elevation, and

Fig. 4 a longitudinal section on line H of Fig. 1.

Fig. 5 is an end elevation, and F Fig. 6 a cross section on line 66 of Fig. 7 showing one end of the blank from which the tread may be made.

Fig. 8 is a small detail showing the way in which the treads are used.

It being understood that the other end of the blank in its preferred form is like that shown in Fig. 7, my invention comprises a face plate A having front and back flanges B and end flanges C, the dotted lines 5, b and c, 0 indicating the lines along which the flanges are bent to form the completed step. It will be noted that the front and back flanges have extensions B B (see Fig. 7).

The completed step as shown in the other views comprises, also, flanged, transverse braces D, of which three are shown, riveted at (Z to the face of the step and at (1 through their end flanges to the flanges B. In the complete steps, also, the extensions B are bent around to engage the flange C and both they and the flange O are provided with openings 0 by which the tread as a whole may be attached to the side pieces or stringers F by which the treads are supported. This attachment of the flanges C, reinforced by the overlapping extension 13, is preferably effected by bolts a passing through said reinforced flanges C and said side pieces or stringers F, as will be understood from Fig. 8. It will also be noted that the front and back flanges B are wider at the point 5 than at their end, this extra width giving additional support, after the manner of a girder, to the face of the tread at a point where it would receive the greatest strain, that is, midway between its points of attachment to the stringers. In addition the main plate or face of the step may be provided with a safety tread E comprising flanges 6 between which an abrasive or non-slipping material may be applied in the usual manner. This construction is so well known that it need not be further described.

Methods of constructing this device will suggest themselves to those skilled in the art, but one advantage of my structure is that the stair tread may be shaped by a single operation from a plate of the character shown in Fig. 7. Each plate may or may not have been provided with flanges e to receive the non-slipping material 6 The tread being properly shaped, that is, its flanges B and C being turned down to define the tread proper, the extensions B are next turned at right angles to the flanges B and are then riveted or otherwise attached to the flanges C, or what is simpler, having been provided with suitable holes, the tread as a whole may then be bolted to the side rails. The braces D, when used, are riveted in place.

Drain holes 6 are preferably provided to prevent the collection of water on the tread.

While other means may be provided for giving to the tread its necessary strength, the form of construction shown and above described enables a comparatively thin sheet metal to be used, from which the tread may be died out, the flanges B andC giving to the thin face of the tread the necessary strength on the four sides to withstand a very heavy strain, this strength being added to by the braces D.

WVhat I claim as my invention is 1. A stair tread comprising a rectangular sheet metal face plate having integral depending flanges at each end thereof and also at the front and back thereof, said front and back flanges having integral extensions which are bent around outside of said end flanges and so as to overlap and reinforce the latter.

2. A stair tread comprising a rectangular sheet-metal face plate having integral depending flanges at each end thereof and also at the front and back thereof, said front and back flanges having integral extensions which are bent around outside of said end flanges so as to overlap and reinforce the latter, said front and back flanges being Wider at their middle parts than at their ends, to form girder-like supports to front and back of the face plate.

A stair tread comprising a rectangular sheet-metal face plate having integral depending flanges at each end thereof and also at the front and back thereof, said front and back flanges having integral extensions which are bent around outside of said end flanges so as to overlap and reinforce the latter, said tread having flanged, transverse braces attached to the face plate and to the front and back flanges to distribute the strain upon the longitudinal portion of the face plate between its edges. M

4;. A stairway comprising side pieces or stringers and a series of rectangular stair treads, each of said stair treads consisting of a piece of sheet metal having integral depending flanges at its ends and also at its front and back sides, said front and back flanges having extensions overlapping and reinforcing said end flanges, and attaching bolts passing through said reinforced end flanges and serving to secure the tread to said side pieces or stringers.

5. A stairway comprising side pieces or stringers and a series of rectangula'r stair treads, each of said stair treads consisting of a piece of sheet metal having integral de pending flanges at its ends and also at its front and back sides, said front and back flanges having extensions overlapping and reinforcing said end flanges, each stair tread having a plurality of flanged, trans verse braces attached to its under side, and attaching bolts passing through said reinforced ond flanges and serving to secure the tread to said sidepieces or strin ers,

CHARLES E. O IVER. 

